WO1988001015A1

WO1988001015A1 - Method for monitoring the propulsion and energy production of a ship

Info

Publication number: WO1988001015A1
Application number: PCT/FR1987/000295
Authority: WO
Inventors: Gérard BOURGAULT; Jean Chamois; Jacques Emery
Original assignee: Elf France
Priority date: 1986-07-31
Filing date: 1987-07-28
Publication date: 1988-02-11
Also published as: FR2602350B1; FR2602350A1

Abstract

Method for monitoring the installation for the propulsion and energy production of a ship of the mechanical propulsion type, according to which the various elements of the installation are fictitiously gathered into groups which may be each controlled by a single parameter.

Description

Method for monitoring the propulsion and energy production of a ship

The present invention relates to a method for monitoring the propulsion installation and energy production of a mechanically propelled ship. It relates in particular to a process which makes it possible to monitor energy efficiency. This monitoring is a necessity if we want to drive a machine installation, such as a machine installation of a motor oil tanker. This monitoring is not easy to carry out on ships due to the absence, in general, of the various elements necessary for the calculation. In addition, it is a service that requires an enormous amount of time from the competent personnel, all the more so as the technicality of the vessels increases.

One of the first objects of the invention is to carry out a process which makes it possible to monitor the efficiency of the machine installation in a suitable manner. This process can be considered as automatic monitoring in real time which is entirely justified, given that it can be accepted that serious monitoring of machine performance improves driving by reducing by at least 2% fuel consumption, which can represent at least 250 tonnes per year for a 90,000 tonnes (deadweight) motor oil tanker operated at 15,000 hp. The process for monitoring the propulsion and energy production installation according to the invention must mainly perform the following functions:

- centralization and processing in real time of the measurements relating to the energy flow and the operating state of the on-board energy equipment, - the calculation of the performance of the various links which constitute the ship's energy chain,

- the comparison of these performances with standards. - development of automatic diagnostics and operator guide.

- the storage of the information acquired for archiving and subsequent processing. These various objectives are achieved by a process for monitoring the propulsion installation and energy production of a mechanically propelled ship, said installation comprising means allowing the transformation of primary energy into mechanical, thermal or electrical energy, said method being characterized in that said means are grouped in a fictitious manner into groups, the energy performance of all the means of each group can be represented by the same quantity and in that, for each group, it is acquired in time real measurements representative of the energy state of the group, we develop from these measurements a quantity representative of the energy state of the group, we evaluate the difference existing between this last quantity and a standard quantity, according to this difference we act on group management variables to make said deviation less than a predetermined value.

According to a preferred embodiment of the invention, the installation that we want to control comprises: - a propulsion group essentially consisting of at least one diesel propulsion engine, supplied with fuel and air, the air supply possibly done via a turbo-compressor,

a recovery group consisting essentially of a boiler for recovering calories from the exhaust gases from the engine, said boiler producing steam,

an auxiliary group comprising at least one auxiliary boiler allowing the accumulation of the steam produced by the recovery group and its evacuation or the production and evacuation of the vapors; - an energy production group, powered by steam from the auxiliary group and comprising at least one turbo-alternator for the production of electrical energy and at least one heat exchanger, the steam outputs of which are connected to the recovery group. The method is then characterized in that for each of these groups, a parameter representative of the operation of all the constituents of the group is developed, this parameter is compared to a set value so as to develop a signal representative of the proper functioning of the group, and as a function of this last signal, action is taken on the group's driving variables to make said deviation less than a predetermined value.

However, the invention and its advantages will be better understood on reading the following description, given in an illustrative and in no way limiting manner, with reference to the appended figures in which:

FIG. 1 schematically represents the principle of the installation for producing energy from an oil tanker, FIG. 2 represents the grouping according to the invention of the means represented in FIG. 1,

FIG. 3 represents the consumption curve of the propulsion unit,

FIG. 4 represents the variation of the heat exchange coefficient in the recovery assembly,

FIG. 5 represents a part of the energy production group,

- Figure 6 shows the steam consumption curve of the turbo alternator as a function of power. FIG. 1 schematically shows the principle of the installation for producing energy from an oil tanker, supplied with fuel. This installation comprises a diesel engine (1) supplied with fuel (3) for driving the propeller (2). The evacuation of the burnt gases from the engine itself feeds a recovery boiler (4) which allows the production of steam. This steam is stored in a tank (5) which can also be supplied by an auxiliary boiler (6). The cover (5) also supplies an energy production group (7) constituted by a set of reheaters which allows the reheating necessary for the main engine (8) the reheating (9) necessary for the auxiliary boiler (6) reheating ( 10) domestic installations and heating of the cargo (11).

The steam tank also supplies turbines (12) for driving pumps (13) as well as winches (14) and a turbo-alternator (15) for the production of electricity.

There is shown in Figure 2 the grouping according to the invention, means shown in Figure 1 which have the same references, as well as complementary elements associated with them.

The first group (100) that can be called propulsion group, includes the diesel engine (1), associated with the propeller (2) and its power system. This supply system consists of a fuel supply (3), an air supply (101) which includes a pump (102) and a refrigeration system (103). The pump (102) is supercharged by a turbo-compressor (104) itself connected to the engine (1) by a pipe (105). The engine (104) comprises a pipe (106) for evacuating the gases to the second group.

The second group (200), which is a recovery group, comprises the recovery boiler (4) and an economizer (201). The boiler (4) is connected to the manifold (106) and its exhaust gas discharge manifold (202) is connected to the economizer (201). The boiler (4) and the economizer (201) each have a steam outlet pipe (206) and (207) which opens into the tank (5). This cover (5) is itself part of a boiler (6) which is contained in the auxiliary module (300). This auxiliary module also includes a pump (209) for the recirculation of hot water from the boiler (6) which is itself provided with a device (not shown) for supplying fuel.

It comprises a pipe (210) for evacuating the steam to the energy production module (7). All the elements contained in the energy production group (7) are supplied with steam by the pipe (210). The power generation group comprises a turbo generator assembly for producing electricity, itself constituted by a turbo generator (215), a discharge pipe (216) and a condenser (217). The turbo alternator is connected to the condenser by the pipe (218). The vacuum condenser is connected to a food cover (219) by a tube (220) which allows the recovery of the condensed vapor. The heating assemblies for the main engine for heating the auxiliary boiler and for heating domestic hot water for the hotel are represented by the reference (220). They are located in parallel with the cargo warming assembly (11). These two assemblies (220) and (11) are connected to the steam pipe (210) and at the outlet emerge from the food tank (219) through an observation box (230) and three pipes (231 , 232, 233). The water heating assembly (10) is supplied by the tubing (210) and opens into the food cover (219) through the tubing (235).

The cargo pump control assembly (12) is supplied with steam via the pipe (210) and opens into the tank (219) through the pipe (236) and the condenser (237). The winch control assembly (14) is also supplied by the tubing (210) and opens into the food cover (219) through the tubing (238).

The condensed steam coming from the food cover (219) is evacuated by the pump (240) and the tube (241) to the assembly (201) for preheating water via a heater (242). Each of the groups, or modules, thus represented is monitored by a single parameter in the manner which will be explained below.

To control the powertrain, we will monitor its consumption according to its power. For this, a theoretical curve is established as shown in FIG. 3. This curve represents the variation in consumption as a function of the power supplied by the engine. To monitor the powerplant, you measure its actual consumption in 24 hours at a given time. We get the point (120). Before carrying out any comparison with the standard, corrections are made to this parameter which are necessary for carrying out the comparison under good conditions; these corrections can, for example, take into account the state of wear of the material, the temperature of the sea water, the air temperature, the calorific value of the fuel, etc.

We then obtain the point (121) which represents the corrected consumption. The difference between the corrected consumption and the theoretical consumption is then calculated. Preferably, this difference is converted into a percentage and it is followed. This difference is recalculated every quarter of an hour. The comparison of this deviation with a standard deviation makes it possible to determine at all times the proper functioning of the propulsion unit, and thus the proper functioning of all the elements of this propulsion unit.

Different adaptations have been tested. In particular, these calculations can only be made in special circumstances provided that stable measurements are obtained.

To monitor the recovery assembly (4), we will monitor the variation in the heat exchange coefficient as a function of the smoke flow. Figure 4 represents the theoretical curve of this variation. This monitoring mode by developing a real point then corrected then compared to the theoretical point, allows to follow very easily the evolution of fouling of the exchangers included in the assembly (4), and therefore of detecting any anomaly, for example any anomaly linked to fouling problems. We can therefore easily predict the sweeping dates.

In the same way, we will monitor the assembly (5) of auxiliary steam production by monitoring the efficiency of the boiler as a function of the steam flow. With regard to the energy production assembly, we will monitor the auxiliary heaters by monitoring the flow of steam produced as a function of the engine power. The correction will be made according to the sea water temperature.

But in this assembly, we will more particularly monitor the electrical energy production assembly using the following installation shown in FIG. 5.

We recognize in this figure the same elements as those of Figure 2, namely the turbo-alternator assembly (215), the discharge pipe (216), the condenser (217) connected to the turbo by the pipe (218), and the tubing (220) ensuring the connection between the condenser (217) and the food cover (219). The discharge pipe (216) is provided with a controlled valve (240). Downstream of the condenser (217), the tubing (210) is provided with a measuring device (241) allowing the measurement of the vapor flow rate.

In normal operation, that is to say when the steam flow rate in the discharge pipe (216) is zero - valve (240) closed -, the turbo-generator is monitored by measuring the steam consumption with respect to the power supplied; the steam consumption being known by measuring the flow rate on the pipe (210). The monitoring curve is represented in figure (6) by the reference (242). This consumption is noted d0.

When the discharge valve is open, the flow of steam through the manifold (210) increases and takes the value d1. To monitor the discharge rate and therefore monitor the operation of the turbo-generator, the difference between d1 and d0 is calculated, d0 being the last known value of the flow rate before the discharge. Optionally, this value d0 is corrected as a function of the power supplied (curve 242).

Claims

1 - Method for monitoring the propulsion installation and energy production of a mechanically propelled ship, said installation comprising means allowing the transformation of a primary energy source into mechanical, thermal or electrical energy, said process being characterized in that said means are grouped in a fictitious manner into groups, the energy performance of all the means of each group being able to be represented by the same quantity and in that for each group, we acquire in real time measurements representative of the energy state of the group, we develop from these measurements a quantity representative of the energy state of the group, we evaluate the difference existing between this last quantity and a standard quantity, according to this difference, we acts on the group's driving variables to make said deviation less than a predetermined value.

2 - Method for monitoring and controlling the propulsion installation and energy production of a mechanically propelled ship, said installation comprising: - a propulsion unit essentially consisting of at least one diesel propulsion engine, supplied with fuel and air, the air supply being via a turbo-compressor,

a recovery group consisting essentially of a boiler for recovering calories from the engine exhaust gases, said boiler producing steam,

an auxiliary group comprising at least one auxiliary boiler allowing the storage of the vapor produced by the recovery group and its evacuation or the production and evacuation of the vapors, an energy production group. powered by steam, evacuated by said auxiliary group and comprising at least one turbo-alternator for the production of electrical energy and at least one heat exchanger whose outputs are connected to the group, characterized in that for each of these groups, a parameter representative of the operation of all the constituents of the group is developed, this parameter is compared to a set value so as to draw up a signal representative of proper functioning of the group, and as a function of this latter signal, the driving variables are acted upon of the group to make said difference less than a predetermined value. - Monitoring method according to claim 2, characterized in that the parameter representative of the operation of the propulsion unit consists of consumption as a function of power. - Method according to claim 2, characterized in that the parameter allowing the monitoring of the recovery group consists of the variation of the heat exchange coefficient as a function of the smoke flow. - Monitoring method according to claim 2, characterized in that the parameter allowing monitoring of the auxiliary production assembly consists of the efficiency of the boiler as a function of the steam flow. - Method according to claim 2, characterized in that the parameter representative of the operation of the energy production assembly is constituted by the variation of the steam flow produced as a function of the power of the engine.